Photocopier cycling apparatus



Feb. 4, 1969 K. J. WHITE PHOTOCOPIER CYCLING APPARATUS I 7 Filed Oct.17. 1966 Sheet of 4 Feb. 4, 1969 K. J. WHITE PHOTOCOPIER CYCLINGAPPARATUS Filed Oct. 17, 1966 Sheet 36 7\ 72 7566;? g} i Eil- Lg] a? Li]PAPER FEED AT CUTTER 22 VAC. 24

FIG.2

BELT w. /E-ILI Q U 7 s 0 w H m 5 D WW; mmw z mama 0 xw 2 7 M W r. EJJQQQ w MV o -7% 3 Feb. 4, 1969 K. J. WHITE PHOTOCOPIER CYCLINGAPPARATUS Sheet Filed Oct. 17, 1966 FIG. 4

lHvpcl jcoa FIG/1H Feb. 4, 1969 K! J. WHITE PHOTOCOPIER CYCLINGAPPARATUS Sheet Fil ed Oct. 17. 1966 FIG.5

United States Patent 7 Claims This invention relates to photographicapparatus for making copies of original subject matter such as documentsby focussing an image of the original upon a sheet of photosensitiverecord material, and particularly to apparatus in which sheets ofdifferent lengths are repeatedly fed to a printing station.

In a typical oflice copier, for example, an original is placed face-downupon a glass platen or like record window, illuminated, and an image ofthe original is projected upon an image plane where it exposes aphotosensitive sheet such as electrostatically sensitized paper. Thesheet is fed to and from the image plane before and after exposure.Because a practical office copier must be able to accommodate differentsizes of original documents, typically 11 in. letter-size originals and14 in. legal-size originals, provision must be made for cutting theproper length of photosensitive sheet from a supply strip prior toexposure. The number of copies which can be made each minute in anycopier is largely dependent on the gap between successively fed sheets.If the same feed interval (leading edge to leading edge) is allowed for11 in. sheets, the gap between 11 in. sheets is three inches greaterthan that between 14 in. sheets, and the speed of printing successive 11in. sheets is limited to the speed of printing 14 in. sheets. Thisresults in an unnecessary loss of time proportional to the extra threeinches of gap between 11 in. sheets.

The object of the present invention is to eliminate unnecessary spacingbetween successive shorter, 11 in., sheets.

According to the invention a copier apparatus comprises means to feed astrip of recording paper from a supply roll at a predetermined speed;cutter means for severing a selected length of paper from the strip;cycling means for actuating said strip feed and cutter means atsuccessive points of its cycle; means for driving said cycling means atdifferent speeds dependent on the length desired to be severed, andmeans for selecting the speed of said driving means thereby to selectthe length to be severed, whereby shorter lengths of paper may be fedand severed in shorter times than longer lengths.

For the purpose of illustration a typical embodiment of the invention isshown in the accompanying drawings in which:

FIG. 1 is an elevation, shown partly in section, of photocopyingapparatus;

FIGS. 1A and 1B are elevations of details of FIG. 1;

FIG. 2 is a schematic diagram of the mechanism of the apparatus;

FIG. 3 is a time graph of the cycle of cams shown in FIG. 2;

FIG. 4A is a schematic diagram of the electrical circuits of theapparatus of FIG. 1;

FIGS. 4 and 5 are schematic diagrams of the electrical circuits of theapparatus of FIG. 1; and

FIG. 6 is an isometric view of part of the apparatus of FIG. 1.

MECHANISM AND OPTICS (FIGS. 1 AND 2) Operator controls Briefly, to makea copy with the illustrated apparatus the operator first passes a liftkey S31 at the front (right side) of the apparatus causing a cover 12 tolift up from a glass platen 1. An 11 in. original document is thenplaced face down on the platen with one end against a movable stop 511.For a 14 in. document, the stop 511 is removed and the document endplaced against a fixed stop 514. The operator then adjusts a rheostat R(FIG. 1A) which controls the light intensity for proper exposure of theoriginal, and then presses either of two print keys S9 or S29 dependingon whether the original is 11 in. or 14 in. long. The cover 12 thencloses, exposes a photosensitive sheet of 11 in. or 14 in. length anddelivers it developed through an exit roll 33. If only a single copy isto be printed the cover then rises uncovering the original. After ashort delay the cover then closes. If a given number of copies aredesired the operator turns a numbered control knob 81 to its appropriateposition before pressing a print key and the cover 12 does not riseuntil the desired number of copies are printed. Or if it is desired toprint copies continuously, the knob 81 is turned to and locked in a Cposition prior to pressing a print key. The copier will then printcopies continuously, without raising the cover, until the control knobis unlocked and returned .to 1 position.

Optics The original, face-down on the glass platen or record window 1,is illuminated from below the platen by a light box comprising twoelongate flash lamps 6 located in curved reflectors 11. Light from thelamps is directed by diffuse reflecting end walls 8 and 9 and specularlyreflecting end walls 7 upon the platen and the original an image of theoriginal is focussed by a lens 3 at the bottom of the light box upon animage plane 2 to which a photosensitive sheet is fed. At the instant thesheet, moving at about 400 feet per minute, is registered with the imagethe lamps 6 are flashed for under a half a second photographically,stopping movement of the sheet relative to the image.

Preferably the original is illuminated by the light box in a patternmore bright at its corners and edges than at its center so that thelight attrition of the lens is compensated, and the image at the plane 2is evenly illuminated throughout its area. The stops 511 and 514 on theplaten are located so that an 11 in. or 14 in. original will be centeredin the illumination pattern of the light box on the central axis 3A ofthe lens 3. Sensitive switches S19 and S20 are placed in the path of thepaper sheets along the image plane 2. As will be explained more fully,when the one of these switches selected by print key S9 or S29 istripped by the leading edge of a moving photosensitive sheet the lamps 6are immediately flashed. The first sensitive switch S19 is located suchthat when it is tripped by the leading edge of an 11 in. sheet, the 11in. sheet is at a position registered with the corresponding position ofan 11 in. original against stop 511 on the platen 1, that is, centeredon the image and on the folded central axis 3A of the lens. Similarly,when switch S20 is tripped by a 14 in. sheet, the sheet is registeredwith the 14 in. image and centered on the axis 3A at the instant ofexposure.

Feeding and cutting mechanism Briefly, print paper having anelectrostatically sensitizable coating is fed from a supply roll 21 to acutter 23 when it cut into 11 in. or 14 in. sheets 21. Concomitantlywith the feed to the cutter the sheets are fed past a pre-exposure lamp20 for dissipating accidental charges on the paper, and thence through ahigh voltage corona discharge device 19 for placing a uniformelectrostatic charge over the paper coating. The severed sheets are fedby rolls 22 before the cutter to a porous belt 24 through which air isdrawn into a vacuum plate 25 connected to a vacuum pump 24. The belt 24carries the severed sheet along the image plane 2 to the paper sensingswitches S19 and S20 where the sensitized paper is exposed. Thence thepaper is fed by a roll 26 into a developer 31 comprising a reservoir 47of developer or electrostatic toner fiuid and a tray 48 through whichthe paper passes. Toner is supplied from the reservoir 47 by a pump M3to the the tray 48 from which it spills back into the reservoir. A floatswitch S senses depletion of toner from the reservoir 47. An intensifiersupply 50 of concentrated toner actuated by a solenoid K33 may beactuated manually or automatically to' increase the concentration of thetoner in the reservoir 47. Beyond the developer 31 the sheet is fed byrolls 28 to a drier 32, and thence by rolls 29 to an exit roll 33. Atthe exit roll 33 the paper sheet is sensed by a switch S30 with a finger30 which normally rides in a groove 33 in the roll 33, the switch S30being actuated when a sheet on the roll lifts the finger from thegroove. Beyond the exit roll 33 an exit switch S22 senses the arrival ofpaper at the exit.

After leaving the supply roll 21 the paper passes over an idler roll 16on a dancer arm 17. If the paper roll 21 is exhausted or the paperbreaks, the dancer arm drops actuating a paper empty switch S24 andswings a connected hook 17 under a cam follower roll 36'. The camfollower roll 36 rides on a cutter cam 36 and is part of a crank 23'carrying the paper cutter blade 23. The cam 36, rotated on a cam shaft35 driven at one of two speeds through clutches CL5 or CL6, allows thespring-urged crank 23 to drive the cutter blade 23 through the paper 21severing sheets 21 therefrom in lengths of 11 in. or 14 in. as will bedescribed under the heading Print Cycle.

The rolls 22 feeding the paper to the cutter 23 are controlled by acombination electromagnetic brake B1 and clutch CL2. The rolls 28 at thedrier 32 are controlled by an electromagnetic clutch CL4.

The mechanisms so far described are driven by a motor M1 through asprocket chain 71 and sprockets 72 as shown in FIG. 2. One sprocket 72drives sprockets 73 and 74 at different speeds. These sprockets arealternatively connected by electromagnetic clutches CL5 and CL6 to a camshaft 35 to drive the cam shaft at one of two speeds. Mounted on the camshaft are the cutter cam 36, and additional cams 71, 72, 75, 76 and 77respectively actuating switches S1, S2, S5, S6 and S7 in a cycle shownin FIG. 3.

In addition the cam shaft 35 drives the multiple copy control knob 81through a step down gear box 86, a shaft 84, a slip clutch 83 and ashaft 82. The control knob 81 has a C position and numbered positionsfrom 1 to 25. When turned to a numbered position other than 1 the knob81 actuates a switch S13. The step down ratio of the gear box 86 is suchthat the knob 81 makes one rotary step from number to number back toward1 (see FIG. 1A) for each 360 cycle of the cam shaft 35. Also the knob 81may be held by a lock 87 in a C position actuating the switch 513 butpreventing rotation of the knob. The slip clutch 83 yields when the knobis in the 1 or C position, and when the knob is manually turned from 1to a higher numbered position.

Other mechanisms The platen cover is raised and lowered by a motor MS asdescribed under the heading Platen Cover Operation. A blower M4 isassociated with the drier 32 as are thermostatic switches and heatersshown schematically in FIG. 5 and described under the heading AuxiliaryCircuits.

PLATEN COVER OPERATION (FIGS. 1 and 6) The cover 12 comprises a blanket51 detachabl hinged by pins 52 to the copier frame 50 at one end of theplaten 1. A rod 53 slides lengthwise of the blanket in a sleeve 54 fixedto the blanket. A thumb screw 56 extending through a slot 57 in thesleeve sets the rod extended from the sleeve as shown, or when losened,allows the rod to be retracted in the sleeve for removal of the coverfrom the frame.

In operation the rod extends through the frame to a crank 58 having twospaced arms 59 and 61 coupled by a spring 62 and pivoted on a bracket63. The cover lift arm 59 carries a roller 64 hearing on the rod 53. Thecrank arm 61 is engaged by a roller 66 mounted eccentrically on a disc67. The disc is driven by a lift motor M5 through a reduction gear box68 and a shaft 69. The shaft 69 carries a cam 71 having a groove 72which closes two sensitive switches S25 and S26 at different positionsof the shaft. UP switch S25 is opposite the groove and is closed exceptwhen the blanket has opened to its limit of about 55 relative to theplaten 1. DOWN switch S26 is closed except when the blanket is closed onthe platen.

Rotation of the shaft causes the eccentric roller 66 to depress crankarm 61 which, through the spring 62, depresses crank 59 and rod 53thereby swinging the blanket 51 off the platen 1. Further rotation ofthe shaft lowers the blanket. Operation of the blanket is initiated by alift key S31. Manually depressing the cover when open does not damagethe rod 53 or associated structure, because the spring coupling 62 willyield.

With the control circuit of FIG. 4 in stand-by the lift key S31 ispressed momentarily, charging a 200 microfarad capacitor C8 in parallelwith a 10 kilohm DC relay K40 and its rectifier D5 across thealternating current busses A and C. Relay K40 is energized transferringits contacts k40A and k40B. Current then flows from the bus A throughcontact 40A and the cover UP switch S25 to the cover lift motor M5causing the blanket to be lifted fully by the crank 58 on shaft 69.After transfer of contact k40A the lift key S31 has no effect. As soonas the shaft 69 turns, the DOWN switch S26 closes. DOWN switch S26 andUP switch S25 remain closed until the cover is fully lifted. At thattime the cover lift shaft cam 71 opens the UP switch S25 stopping thelift motor M5.

Capacitor C8 discharges shortly after the cover is raised during a 5second interval determined by the value of the capacitor and relay coil.The charge bleeds through the relay K40, and K40 is then deenergizedre-transferring its contacts to the position shown. The operator maythen lay an original document on the platen under the opened cover. Hethen presses one of two double pole print keys S9 or S29, depending onthe length of the original to be copied. Key S9 is pressed for an 11in., letter-size original, key $29 for a 14 in., legal-size original.

At the start of the print cycle, described more fully hereinafter,relays K9, K10 and K23 are energized, the latter closing contact k23 andsupplying power to the third bus A. A time delay relay K61 is thenenergized and closes its contact k61 after 2 seconds and supplies powerto the cover motor M5 through contact M013 and now closed sensitiveswitch S26. The motor lowers the blanket to the platen and is thenturned off by opening the sensitive switch S26. During the print cycleinitiated by closing one of the print keys S9 or S29 a cam switch 57A isclosed energizing a relay K41 during a period of about 2 secondsdeter-mined by the time constant of its resistance (10 kilohms) and thecapacitance of a parallel capacitor C9, and transferring its contact M1to connect capacitor C8 to the A" bus. Capacitor C8 is charged withoutenergizing its parallel relay K40, and when, after exposure, cam switchS7A retransfers deenergizing relay K41, contact k41 returns to theposition shown, and capacitor C8 discharges through and energizes relayK40. The capacitor discharges for an interval of over two secondsthrough the relay coil transferring contacts k40A and k40B, the formerof which completes a connection from the secondary bus A throughsensitive switch S25 and the cover motor M5. The motor raises the coverclosing sensitive switch S26 and, when the cover is raised, openingswitch S25. The discharge of capacitor C8 continues long enough to allowthe operator to remove the document just copied and to place another onthe platen. Then, when the discharge is complete K40 is deenergizedtransferring its contacts k40A and k40B to the position shown in FIG. 4and completing a circuit through contact k40B, switch S26 and the covermotor which lowers the cover to the platen, closes switch S25 and, whenthe cover is lowered, opens switch S26. The cycle is then complete, anda new print cycle may be started by pressing one of the print keys S9 orS29. If a new print cycle is not started the tertiary bus A" isdisconnected by opening of relay contact k23, as is explained more fullyunder the heading Print Cycle.

When the control knob 81 is in C or a numbered position other than 1,the switch 813B transferred by the knob bypasses cam switch S7A holdingrelay K41 energized and contact k41 transferred and preventing dischargeof capacitor C8 through relay K40. When switch S138 is opened when thecontrol knob 81 returns to 1, subsequent operation of cam switch S7Bcauses the cover raising previously described.

PRINT CYCLE (FIGS. 1 TO 4) The copier is capable of printing a singlecopy of each original. Also, if the Multiple Copy control '81 is setotherwise, a selected multiple of the original is printed automatically,or the copier may be set to print continuously either one or successiveoriginals. Following is a description of a single print cycle. Automaticprinting is described under the sub-heading :Multiple & ContinuousCycling. Other components not entering directly into the print cycle areshown in FIG. 5 and described under the heading Auxiliary Circuits.

Single print cycle With an original document on the platen or copywindow 1, and with the cover :12 lowered on the platen, feeding, cuttingand exposure of the print paper is initiated by either the 11 in. PRINTkey S9 or the 14 in. PRINT key S29 selected by the operator according tothe siez of the original. Closing the ganged contacts 89A and 89B of keyS9 energizes the latch coil K60L of a latching relay K60, which includesa reset coil K60R, and throws contacts k60A, k60B and k60C to, andlatches them in, the position shown in FIG. 4 if they are not sotransferred. Alternatively, the ganged contacts 829A and 529B of key S29energize the reset coil K60R transferring contacts to, and latching themin, the position not shown.

Closing either key S9 or S29 also energies a primary start relay coilK9, closing its contacts k9A, k9B and k9C. Contact k9A completes aconnection from the secondary bus A holding relay K9 energized until camswitch S6 opens later disconnecting bus A. Contact k9B charges acapacitor C3 with curernt rectified by a diode D4 and resistor R1 of asecondary start relay K10 by a connection from the main power bus Athrough the coil K10, a switch 24, switch S15 and relay contact k31C tothe common bus C. The contact k10, closed when relay K10 is energized,energizes a main power relay K23 through contact k31A of relay K31.Contact k23, then closed by relay K23, connects the main power bus A tothe tertiary bus A. Components shown in FIG. 5 and described under theheading Auxiliary Circuits are then energized. But primarily contact k23energizes the main motor Mll thereby driving the non-clutched paper feedrolls and belt and the cam shaft 35, and supplies current through A" tocam switch S1 or S2, of later significance, and through now closed relaycontact k9C to clutch CL5 or CL6, whichever has been selected by contactk60B of latching relay K60. As previously explained, relay K60 islatched either in L or R position depending on whether print switch S9(for an 11 in. original) or S29 (for a 14 in. original) has been pressedto start the print cycle. Whichever of clutches CLS or CL 6 isenergized, the corresponding sprocket 73 or 74 is now (time t in FIG. 3)

connected to the cam shaft 35 to begin to drive it at one of two speeds.For an 11 in. original document the drive speed of sprocket 73 isfaster. Because the paper feed rolls 22 just beyond the paper supplyroll 21 are not yet clutched by CL2, paper feed does not begin untilafter the cam shaft 35 starts turning at time t0 (FIG. 6).

At time 11 cam switches S1, S2, S and S7 are transferred from thepositions shown in FIG. 4 with the following six effects:

(1) Cam switches S1 and S2 break the connection from bus A to thebraking coil B1 of a combined brakeclutch B1-CL2, and energize theclutch coil CL2 connecting the corresponding main drive sprocket 72 tothe paper feed rolls 22 at the paper cutter 23. Paper feed through thecutter to the suction belt 24 is thus started.

(2) Closing of cam switch SSB completes a holding circuit for energizedrelay K10.

(3) Cam switch SSA, through S13A, energizes the transformer T9 of thehigh voltage power supply 19' for corona paper sensitizer 19 (see FIGURE4A) and the paper pre-exposing lamp 20, and directly energizes the Lcoil of a latching relay K30L. The relay contact k30 then closes,energizing a time delay relay K31 which does not close its contact k31for an interval of about five seconds, longer than the normal time fromthe start of the print cycle until the discharge of a print past theexit switch S31. In the event that a print becomes jammed in its pathand cannot trip the exit switch within five seconds, closing of contactk3-1 initiates a stopping sequence described under the headingMalfunctions.

(4) Closing of a cam switch SSE at time r1 bypasses switch S24,malfunction switch S15 and the time delay relay contact k31C during theprint paper feeding, cutting and exposing portions of the print cycle,to avoid interruption of these operations once they have begun.

(5) Closing of cam switch S7A bypasses relay contact k9C which is openedat time 12.

(6) Closing of cam switch S7B holds energized relay K23, which in turnholds the tertiary bus A energized even if relay K31 should open itscontact k31A. This insures that the paper feed and cam shaft drive willcomplete feeding and cutting of a sheet of print paper even if a jam ofpaper develops as detected by failure of exit switch S22 to betransferred during the time delay period of relay K31.

At time t2 cam switch S6 alone is transferred from the secondary bus A,as shown in FIG. 4, to its alternate position connecting the main powerbus A to relay K10, thereby holding the relay energized. Disconnectingpower from the secondary bus A deenergizes relay K9 whose contact k9Cwas bypassed at time t1 by cam switch S7A, and also disables the liftswitch S31.

At times t3 cam switches S1 and S2 are returned to the position shown inFIG. 4, deenergizing the clutch CL2 and energizing brake B1 connected tofeed rolls 22 and thereby unclutching and braking the leading end ofpaper from supply roll 21, whose length beyond the cutter 23 isdetermined by the speed at which the cam shaft 35 is driven by clutchCLS or CL6.

At time t4 this length of paper is severed from the supply when thecutter cam 36 actuates the cutter 23. The leading end of the severedsheet of paper is held on the continuously running belt 24 by the vacuumplate 25, and therefore is carried on to the sensitive switches S19 andS20 in the path of the leading edge of the sheet.

At time t4+ the leading edge of the severed sheet successively closesswitches S19 and S20. But only one of these switches is effective,depending on the position of relay contact k60C, which in turn dependson whether the 11 in. print key S9 or the 14 in. print key S29 waspressed to initiate the printing cycle. As shown in FIG. 1 the 11 in.paper switch S19 is in advance of the 14 in. paper switch S20, and isdisposed with respect to the print window 2 such that when S19 istripped an 11 in. sheet of print paper is centered in the print window 2in optical register with an 11 in. original document located on theplaten or record window 1 by the stop 5 and centered on the opticalaxis. Paper switch S20 is so positioned 1 /2 in. beyond switch S19 thatwhen a 14 in. sheet of print paper trips it, the sheet is centered inoptical register with a 14 in. original document located on the platen 1with one edge at the left hand end thereof.

At the instant 24+ when the enabled paper switch S19 or S20 is trippedthe exposure trigger relay K43 is energized and its contact k43Aenergizes a relay K32 in the high voltage supply 100 of the stroboscopicexposing lamps 6. At this instant the original document on the platen isilluminated and its image is focussed on the severed print sheetcentered in the print window 2.

At time t4+ relay contact k43B is also closed, energizing a meter Mwhich counts the number of exposures and periodically replenishes thedeveloper in the developer tray 48 by electromagnetic activation of aliquid developer intensifier dispenser 50. As shown in FIG. 5 theintensifier may also be caused to dispense a dose of intensifier byactuation of a manual switch S33 which activates the coil K33 of theintensifier. Relay contact k43B also initiates a platen cover openingsequence described under the heading Platen Cover Operation.

Following exposure the print that is fed through the developer 31, dryer32 to the exit switch S22 which is tripped by the leading edge of theexiting developed and fixed print. During the developing, drying andexiting a new print cycle may be started. However, the print cycleconcludes with the following cam switch operation.

At time :5 cam switch S6 is returned to the position shown in FIG. 4deenergizing relays K10, and K61 successively and resupplying thesecondary bus A for subsequent operation of the cover lift relay K40 andthe PRINT switches S9 and S29.

At time t6 cam switches SSA, SSB, 557A and S57B return to the startposition shown in FIG. 4. Switch S7B deenergizes relay K23 removingsupply from the tertiary bus MULTIPLE AND CONTINUOUS CYCLING The copyselector operator control 81 comprises a knob normally set at numeral 1for printing a single copy of an original each time the operatorinitiates a print cycle. This dial may be set to print any number ofcopies of the same original up to twenty-five by turning the dial to thecorrespondingly numbered position from which it is stepped back toward 1position as each copy is printed. Or it may be locked in position C soas to print copies continuously until turned from position C.

When set either to C position or a numbered position the cam 62 rotatedby control 61 transfers ganged switches 513A and S1303. Switch S13A,when transferred from the position shown in FIG. 4, breaks theconnection from bus A" through cam switch SSA and 813A to make thetransformer corona sensitizer 20 and pre-exposing lamp, but makes adirect connection from bus A" to the sensitizer and lamp. Thus whilemore than one copy is being made the sensitizer and lamp remaincontinuously energized as sheets of print paper are rapidly fed thereby.Switch 513B bypasses relay contact k9C and maintains the cam shaft 35 incontinuous rotation through clutch CLS or CL6. Thus the copier continuesto execute print cycles until the control knob 81 is stepped back toposition 1 opening switches 813A and 513B.

AUXILIARY CIRCUITS (FIG. 5)

FIG. 5 shows circuits and components auxiliary to the circuits of FIG. 4and includes those continuously supplied by the main power bus A, and bythe tertiary bus A" after K23 is energized at the start of the printcycle.

A humidistat switch S10 responds to excess humidity Within the copierhousing 50 by closing and supplying current to a heater R8 which reduceshumidity. A manual switch S11 within the housing may be closed by aservice man to energize the R coil K30R of the latching relay K30 withthe same resetting effect as transfer of the exit switch S22. A manualswitch S33 may be opearted by a serviceman to energize a relay K33 whichelectromagnetically activates the liquid intensifier dispenser 50 in themanner of meter M described under the heading Print Cycle.

When the tertiary bus A" has been supplied through relay contact k23A atthe start of the print cycle three motors M2, M3 and M4 are continuouslyenergized. A vac- 8 uum is drawn at the plate 25 (FIG. 1) by motor M2.M0- tor M3 pumps toner from the developer tank 47 to the developer tray48. Motor M4 continuously circulates air through the drier 32. Theclutch CL4 is coupled to the paper feed rolls 28 at the drier 32.

Assuming that the apparatus is at ambient temperature, and a themostaticswitch S17 is in the position shown in FIG. 5 a relay K4 is energizedclosing its contact k4 and and supplying 120 volt current to a 1300 wattheater 'RG located in the drier 32. As the temperature rises, thecontact of the thermostatic switch S17 transfers from the position showndeenergizing relay K4 and energizing relay K42. Relay contact k42 thendrops the current supplied R6 to volts. An auxiliary 500 watt heater R7is supplied directly from the tertiary bus A. Both heaters R6 and R7 aredisconnected by overheat thermostatic switches S3 and S4 respectively,in the event that the temperature within the apparatus becomesexcessively high.

MALFUNCTIONS In normal operation the paper supply roll 21 and the papertoner in tank 47 will become exhausted. These conditions are indicatedvisually by lamps P and T in the circuit of FIG. 4. In addition thecircuit prevents or minimizes the effects of such occurrences as jammingof the paper along its path between the cutter 23 and the exit roll 33,wrapping of the paper around the exit roll 33, and failure of circuitcomponents controlling the paper feed clutch CL2 which results infeeding continuous or longer than standard 11 in. or 14 in. sheets. Thecircuit of FIG. 4 also prevents response to a malfunction from stoppingthe paper cutter 23 while it has only partially severed a sheet of printpaper.

Paper exhausted When the last length of paper leaves the supply roll 21the idler roll 16 carried on the dancer arm 17 drops causing the dancerarm to transfer switch S24 and also lifting the cutter bell crank 23'oif its cam 36. On transfer of switch S24 from the position shown aconnection is completed from the primary bus A through the Paper Emptyindicator lamp P, switches S24 and S15 and relay contact .k31C to thecommon bus C. Lighting of lamp P thus visually indicates the exhaustedpaper condition. Transfer of switch S24 also disconnects the commonreturn circuit for brake B1 and clutches CL2, CLS and CL6 when camswitch SSB opens at time t6, the end of the print cycle, after cuttingand exposure of the last full length of paper from the supply roll 21.Thus a subsequent print cycle is prevented until a new supply roll ofpaper has been inserted. A later cycle might start with less than 11 in.length of paper available. Such short lengths are apt to jam along thefeed path, and their feed is prevented by stopping print cyclessubsequent to paper exhaust or breaking. In addition dropping of thedancer arm 17 will swing an attached book 17 under the cutter camfollower roll 36' and prevents the cutter crank 23 from moving thecutter 23 into the paper path.

Toner exhausted Liquid paper toner in the developer tank 47 is slowlyremoved by print sheets until a significant drop in level is detected bythe float switch S15. Transfer of switch S15 then completes a circuitfrom the main bus A through a Toner Empty indicator lamp T, and relaycontact k31C to the common bus C. Lack of adequate toner is thu'visually indicated.

Paper jammed In normal operation a developed sheet of paper willtransfer the exit switch S22 before the time delay relay K31 closes atthe end of the predetermined approximately five seconds delay period.The reset coil K30R of the latching relay is then ener-gezied, openingits contact k30 and stopping and resetting the time delay relay K31. The

print cycle then concludes normally as described at the end of thesection entitled Print Cycle.

Infrequent defects in the print paper may result in the leading edge ofthe paper becoming jammed along its path from the cutter 23 tothe exitroll 33. In this event the exit switch is not tripped by the printedsheet and the time delay period of relay K31 ends with transfer of relaycontacts k31A, k31B and k31C. Unless cam switch S7B is closed, transferof contact k31A will deenergize the auxiliary start relay K23 whoseopening contact k23 removes power supply to the tertiary bus A". If camswitch 87B is closed, relay K23 will remain energized until time t6,allowing the cutter cam 36 to conclude severing a sheet of paper at thecutter 23, and avoiding initiation of a subsequent print cycle with apartially severed sheet at the cutter. Then opening of switch S7B willdeenergize relay K23, cut power to the bus A" and prevent furthermechanical operations until the jam has been cleared.

The necessity for clearing a jam is visually indicated by simultaneousillumination of both lamps T and P upon transfer of relay contacts k31Band k31C which are directly connected to the common bus C. Since it isextremely unlikely that paper and toner will become exhaustedsimultaneously, the dual illumination of lamps P and T is a reliableindication of a jam.

Exit roll wrapping and continuous sheet (cam shaft stopped) It ispossible that an exiting print will trip the exit switch S22 but thenwrap around the exit roll 33. In this event a sensitive switch S30feeling a portion of the exit roll not normally covered senses thewrapped paper and closes until the print is removed. Switch S30 holdsthe time delay relay K31 energized until, at the end of its period, itdeenergizes relay K23, stopping machine operation and lights both lampsT and P as described above.

Other component failures If during the interval from time t (whenclosing switch S9 or S29 initiates the print cycle) to time t1 (when camswitch SSA closes) a trouble develops which prevents turning of the camshaft 35, the auxiliary heaters, blowers and motors shown in FIG. '5 andother components fed by bus A would operate continuously because theprint cycle can not be completed by termination of the cam shaft cycle.Relay K30L would not be energized by cam switch SSA, and relay K31 wouldnot start its timing out cycle to'deenergize K23 and cause contact k23to disconnect power from the tertiary bus A". To prevent this occurrenceduring time to time t1, a connection is provided between the normallyopen contact k9B and the normally closed contact k30. Through thisconnection relay K31 is energized from the primary but A until camswitch S6 at time 22 deenergizes lbus A" and relay K9. By this time camswitch S5 will have closed if operation is normal. If operation isfaulty S6 will not transfer and relay K31 will time out, deenergizerelay K23 and break power through contact k23 to the components suppliedby the tertiary bus A".

Overlength sheet If a circuit component associated with either of thecam drive clutches CLS or CL6 should malfunction during the print cyclebefore cutting is started the paper feed clutch CL2 could continue tofeed paper from the roll 21. Malfunction of switches 87A, switch 13 orrelay K9, or failure of diode D2 or resistor R4 can produce such acondition. To prevent its occurrence a relay K62 is connected inparallel with the clutches CLS and CL6 and is energized with them,closing its contact k62 which enables energization of the paper feedclutch GL2. A malfunction which deenergizes the cam drive clutches CLSand GL6 'will also deenergize relay K62, opening contact k62 anddisabling the feed clutch to stop paper feed.

SUMMARY As previously stated, the object of the present invention is toeliminate :an extra three inch gap between 11 in. sheets which wouldoccur if they were fed at the same frequency as 14 in. sheets. Thisthree inch additional gap is eliminated by spacing the 11 in. sheets atmore frequent intervals than 14 in. sheets so that both 11 in and 14 in.sheets will be fed with the same minimal spacing. The higher frequencyfeeding of the 11 in. sheets is achieved, notwithstanding that they arefed at the same linear speed as the 14 in. sheets, by increasing thespeed of the cam shaft 35 for 11 in. sheet cutting so that it repeatsits cycle at a higher rate than for 14 in. sheet cutting, and thereforecompletes each cutting cycle in a shorter time. For example, as shown inFIG. 3, the cycle of cam shaft 35 is completed in approximately twoseconds for M in. sheets as compared with 216 seconds for 14 in. sheets.The actual time saving is 7 or about one-fifth of the total print cycle.This is a significant increase of printing speed from, for example,thirty 11 in. prints per minute as against twenty-five 14 in. sheets ina copier which feeds the sheets at about 400 feet per minute.Particularly in high speed co piers such a speed increase is startlinglysignificant.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claims.

I claim:

1. Copier apparatus comprising:

means to feed a strip of recording paper from a supply roll at apredetermined speed;

cutter means for severing a selected length of paper from the strip;

cycling means for actuating said strip feed and cutter means atsuccessive points of its cycle;

means for driving said cycling means at different speeds dependent onthe length desired to be severed, and

means for selecting the speed of said driving means thereby to selectthe length to be severed,

whereby shorter lengths of paper may be fed and severed in shorter timesthan longer lengths.

2. Copier apparatus according to claim 1 wherein said selecting meanscomprises at least two switches, one for each length of paper, and atleast two drivers respectively responsive to actuation of said switchesto drive said cycling means at speeds inversely dependent on the lengthof paper to be severed.

3. Copier apparatus according to claim 1 characterized by means to feedsevered lengths to a printing station, means to print successive lengthsfed to said station, and means to cause repeated cycling of said cyclingmeans at said selected speed.

4. Copier apparatus according to claim 2 characterized by means to feedsevered lengths to a printing station, means to print successive lengthsfed to said station, and means to cause repeated cycling of said cyclingmeans at said selected speed.

5. Copier apparatus for reproducing original documents of differentlengths comprising:

means for illuminating the original subject,

means for projecting an image of the original on an image plane,

means to feed a strip of photosensitive paper from a supply roll along apath to said image plane at a predetermined speed,

cutter means on said path for severing sheets from the strip,

means for exposing a sheet to said image in said image plane,

cycling means for actuating said strip feed and cutter means atsuccessive points of its cycle,

means for driving said cycling means at different rates means to printsuccessive lengths fed to said station, and inversely dependent on thelength desired to be means to cause repeated cycling of said cyclingmeans at severed, and said selected speed.

means for selecting the rate of said driving means thereby to select asheet length corresponding to the 5 References Cited length of theoriginal document, UNITED STATES PA whereby shorter sheets may be fedand severed at more '3 282 192 Ill/1966 Chen et a1 9589 frequentIntervals than Sheets 3,289,532 12/1966 Baumgarten et a1 ss-24 6. Copierapparatus according to claim 5 wherein said selecting means comprises atleast two switches, one for each length of paper, and at least twodrivers respectively 10 NORTON A Primary Examine" responsive toactuation of said switches to drive said RICHARD WINT'E'RCORN, AssistantExamine!- cycling means at speeds inversely dependent on the lengthofvpaper to be severed. CL

7. Copier apparatus according to claim 5 characterized 15 95589 by meansto feed severed lengths to a printing station,

5. COPIER APPARATUS FOR REPRODUCING ORIGINAL DOCUMENTS OF DIFFERENTLENGTHS COMPRISING: MEANS FOR ILLUMINATING THE ORIGINAL SUBJECT, MEANSFOR PROJECTING AN IMAGE OF THE ORIGINAL ON AN IMAGE PLANE, MEANS TO FEEDA STRIP OF PHOTOSENSITIVE PAPER FROM A SUPPLY ROLL ALONG A PATH TO SAIDIMAGE PLANE AT A PREDETERMINED SPEED, CUTTER MEANS ON SAID PATH FORSEVERING SHEETS FROM THE STRIP, MEANS FOR EXPOSING A SHEET TO SAID IMAGEIN SAID IMAGE PLANE, CYCLING MEANS FOR ACTUATING SAID STRIP FEED ANDCUTTER MEANS AT SUCCESSIVE POINTS OF ITS CYCLE, MEANS FOR DRIVING SAIDCYCLING MEANS AT DIFFERENT RATES INVERSELY DEPENDENT ON THE LENGTHDESIRED TO BE SEVERED, AND MEANS FOR SELECTING THE RATE OF SAID DRIVINGMEANS THEREBY TO SELECT A SHEET LENGTH CORRESPONDING TO THE LENGTH OFTHE ORIGINAL DOCUMENT, WHEREBY SHORTER SHEETS MAY BE FED AND SEVERED ATMORE FREQUENT INTERVALS THAN LONG SHEETS.